355 speed sensor location? | FerrariChat

355 speed sensor location?

Discussion in '348/355' started by toussi1, Jul 9, 2007.

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  1. toussi1

    toussi1 Karting

    Jun 10, 2007
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    I am having some problems with my speed readings, I want to change my speed sensor which i think is located somwhere under the engine? Anyone have a picture where its located?


    Thanks
     
  2. zero

    zero Guest

    Apr 24, 2007
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    #2 zero, Jul 9, 2007
    Last edited by a moderator: Sep 7, 2017
  3. PAP 348

    PAP 348 Ten Time F1 World Champ
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    #3 PAP 348, Jul 9, 2007
    Last edited by a moderator: Sep 7, 2017
  4. UConn Husky

    UConn Husky F1 Rookie

    Nov 11, 2006
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    I was thinking the same thing, pretty good second post!
     
  5. gothspeed

    gothspeed F1 World Champ

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  6. f355spider

    f355spider F1 World Champ
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    I replaced mine. It is accessed from the top left of the transaxle. When mine went, it stopped completely. Then the lack of speedo signal tripped a suspension light.

    If you are intermittent, I would check the connection on the back of the speedometer (first!), and the connection of the speedo sender.
     
    ShineKen likes this.
  7. ernie

    ernie Two Time F1 World Champ
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    +1

    There are 2 screws that hold the instrument pod in place. Remove those and then lift it straight up. Now you'll have access to the back of the speedometer. Make sure that the connector on the back is clean and making good contact.
     
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  8. toussi1

    toussi1 Karting

    Jun 10, 2007
    160
    USA
    I looked around the engine from up top, couldn't figure out where the sensor is... that picture provided, is that the transmission? Do I have to go under the car to get access to this sensor?
     
  9. 355dreamer

    355dreamer F1 World Champ
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    This thread bothers me... Is there any purpose to this other than to disconnect an the mileage?
     
  10. f355spider

    f355spider F1 World Champ
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    Yes, there is an OBVIOUS purpose, he is trying to fix an intermittent speedometer. I see nothing nefarious here. These speedo sensors break all the time. I fixed it on my 308, 328 and 355. If it bothers you, then look away.

    PS: Every Ferrari made since at least the early 70's uses a electronic speedo sensor that can be found and unplugged in 5 minutes. So common that any potential purchaser should be very adamant about complete records with any Ferrari they purchase. This thread is helping someone with a specific speedometer problem...if someone chooses to misuse the information, so be it...but karma will get them later.
     
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  11. f355spider

    f355spider F1 World Champ
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    No, it is on the left side of the transaxle, but toward the front. It is down low, you will see the pigtail and a black plastic connector up higher...and you can follow that down to the sensor itself.
     
  12. ShineKen

    ShineKen F1 World Champ
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    Been chasing a suspension light. Had to check all the actuators, but they appear to be installed correctly. However, I was also getting a check engine light 1-4 (not sure why it’s on the 1-4 bank). Code is 4123 which is a speedometer signal. Will have to look into it and get it sorted, but good to know a faulty speed sensor and suspension light are related.




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  13. ShineKen

    ShineKen F1 World Champ
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    I’m going to also assume if one disconnects the speed sensor on purpose, the dampers/actuators don’t function properly.
     
  14. f355spider

    f355spider F1 World Champ
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    I believe they stiffen at speed and if the suspension ECU is not receiving a speed signal, its going to default to something...not sure if that would be hard or soft.
     
  15. f355spider

    f355spider F1 World Champ
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    BTW, I had a troublesome suspension light. I had several extra known good actuators I moved around and the light persisted. I double checked the gears on top of each shock and they were present. I took it to the dealer and they confirmed it was my right rear shock. I took it home and pondered the problem...broke out an 8X loupe and inspected the gear on top of the shock again, and low and behold, it was missing a big chunk on the forward side that I hadn't seen. From above it looked all intact, but was actually missing a sizeable piece on the front side that I didn't notice. I had a spare Hill Engineering replacement gear and fixed it right away.
     
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  16. johnk...

    johnk... F1 World Champ
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    I had a speed sensor fail a few years back. Speedometer dropped to 0 mph. No suspension light though. Don't know what effect it had on other things.
     
  17. Portofino

    Portofino Formula Junior

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    Anyone who pays a premium for a low miler Ferrari ( 308, 348 , 355 ) are deluding themselves.
    Thank god the engineering engine wise is durable and modern lubrication actually works in terms of longevity.
     
  18. ShineKen

    ShineKen F1 World Champ
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    My speedometer works and the check engine light disappeared on its own. Not sure if it was a temporary faulty reading, but suspension light is still on after driving around for 10 min. Not sure if I need to drive around longer or attempt to address the speed sensor. These things are going for 500 bucks. Unbelievable.
     
  19. ShineKen

    ShineKen F1 World Champ
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    Did you attempt to fix the speed sensor or did you buy another?
     
  20. f355spider

    f355spider F1 World Champ
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    ShineKen,
    Are you certain your shock actuators are good? I know that by the time I sold by 355, I had replaced two actuators that had failed. I was lucky to have purchased four spares, including shocks and springs, from another Fchatter that put Olins with remote reservoirs on his F355B. Having known good spares allowed me to diagnose which actuator failed whenever I got the light. It was about 50/50 between failed gears on top of the shock and failed actuators.

    The suspension light will go out on its own, once the fault is corrected.
     
  21. johnk...

    johnk... F1 World Champ
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    Replaced it. $224 from Tom Vail All Ferrari Parts, but that was back in April, 2022.
     
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  22. johnk...

    johnk... F1 World Champ
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    Also, I recalled reading this from the WSM for the 2.7 injection but didn't remember where earlier:

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    I don't know what it does. I didn't notice any difference in divisibility when my speed sensor was out.
     
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  23. ShineKen

    ShineKen F1 World Champ
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    Just checked with Tom Vail. $600.
     
  24. ShineKen

    ShineKen F1 World Champ
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    I’ve only had this car for 100 miles and within those 100 miles, I didn’t have a check engine light or suspension light. All the teeth of the actuators are still there. I’m going to assume they are good, but of course not certain.
     
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  25. johnk...

    johnk... F1 World Champ
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    :eek: WOW! We maybe be seeing a lot of 355s with questionable mileage in the future. :rolleyes:
     
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